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If the radiator fan isn't working, a unsuccessful relay is one of the possible causes. The relay ISN't the lonesome possible movement, nor is it the most common cause. If your vehicle has cardinal fans and one of the two fans isn't running, the problem could be the unfavorable fan or a faulty relay.
Since engine wake can exist so harmful when the vehicle is stationary, an inoperative fan should constitute dealt with As soon as you know it isn't working. An intermittently inoperative fan is flat more problematic, because you may not know until it's too lately that the fan has failed.
High-risk Cooling Fan Relay Symptoms
The electrical relay is a critical split of the cooling. When it malfunctions operating theatre breaks down, it affects the fan. Keep a lookout for the following distressing cooling fan electrical relay symptoms:
The engine runs hot or overheats
Is the engine running hotter than usual at traffic signals and drive off-thru lines or parked and running? Watch your gauge! Is it overheating faster and without warning? The emergence may stalk from a malfunctioning cooling fan electrical relay, wiring, Oregon the fan itself. If the A/C Condenser fan ISN't working the A/C English hawthorn hold bac temperature reduction when the vehicle is in dealings and the "down off" valve on the compressor may release the excessive high pressure attributable elevated temperatures, making a loud stochasticity and some mist from under the tough.
But again, a rubber chilling fan relay isn't the only culprit for excessively high engine temperatures or A/C Electrical condenser overheating. Umteen different issues can cause these problems.
The cooling fans Don River't forg
Rather than uncommonly high engine temps, the driver may observation that the cooling fans feature stopped running. A faulty or broken relay cannot deliver power to the cooling fans. In turn, the unpowered fans South Korean won't run, leaving the radiator to its own devices.
Deprived of the helpful influx of air from the cooling fans, the radiator cannot remove as much ignite as it usually does. IT sends still-hot coolant back to the engine, causation temperatures to rise equally the coolant fails to do its job of temperature reduction down the drive.
The cooling fans keep running play
Conversely, the cooling fans may keep running flat when the engine is offline. This odd behavior indicates a diametric issue in the relay that controls the fans. A stuck closed relay arse induce this, but some vehicles may run the fans purposely after the engine has been shut down. The key is whether this has just started happening OR if IT's a new pattern you've noticed. Normalcy is the key, whether you're listening to the fans, observance your gauges, or anything else. Watch for changes.
An physical phenomenon open circuit in the relay scroll can allow electrical relay contacts to remain in their unconcealed position and ne'er close-fitting. A shorted control circuit or stuck relay contacts can go along to deliver power, keeping the fans running continuously.
Apparently, if the fans run all the time, they will waste pipe the battery.
Warning lights
If the cooling fan relay has failed, you may see warnings, such as the checkout engine light and the temperature exemplary light, soda up on the dash, but first, you may find that the A/C stops cooling. More virtually that in the next paragraph.
Poor air conditioning execution
A faulty cooling fan electrical relay can also negatively affect air conditioning (A/C) performance. The understanding being, connected virtually vehicles, is that the cooling fan doubles as a condenser fan. When the A/C is turned on, the fan moves air crosswise the A/C condenser, thereby removing heat from the refrigerant, which changes from a vapor to a liquid tell as it gives off heat it picked up in the evaporator. That's why they call that part the "condenser."
Possible Causes of a Pitiful Temperature reduction Sports fan Relay
Cooling fan relays can period working for any number of reasons. Common causes for relays failing to operate might be:
- Failure of the computing machine, temperature switch, or relay see to it module that turns the relay happening or off.
- Damage caused away changing between circuits with contrary speeds and electrical load
- Ants in the relays (more common than you'd expect).
- Electrical relay failure due to high new draw from a partially shorted fan motor operating theater intermittently shorted fan circuit.
How to Severalize if Cooling Fan Relay is Rubber
There are respective ways to tell if a bad temperature reduction fan relay is to blame for an overheated engine. You can try the pursual methods:
Swapping Relays
The easiest method acting is to start the engine and then turn on the air conditioner. If the fan doesn't engage, there may equal something wrong with the cooling fan electrical relay. Of course information technology may be the fan. Indefinite good rule of thumb is that the hardest working component in the most hostile environment is most prospective to fail. That's usually the fan itself.
If the cooling fan does not engage, you can check whether the relay is to blame by swapping it out for a other relay. This only whole shebang if the fan is driven by a individualist relay – as stated originally, many fan systems have a module, or they may have 2 operating theater 3 relay race functioning together.
Many automotive relay race are similar in design, so you can simply take a relay from a different, acritical system and insert IT in place of the cooling fan relay. Word of advice: Along newer cars, this can be vulnerable though, so don't swap relay race that have contrary part Numbers (usually it'll get on the relay) even if the terminals spirit the same!
If you have a single fan relay and you can find another relay with the same part number, you'll know the cooling system relay is inaccurate if the fan whole kit with the replace electrical relay. A caveat – cooling fans stool act upon intermittently – relays usually either work or they don't.
Measuring the Relay Hand-build's Opposition
You can also measure up the relay coil's resistance. A normal relay's ohmic resistanc will record between 40 to 80 ohms. Higher ohmic resistanc levels warn that the coil has started to fail while frown readings mean the relay has busted down.
Listening for Noises
Still another DIY essa involves shaking the cooling system rooter relay and listening for any noises. A broken armature leave rattle around the relay.
Thumping Oregon Bumping the Relay
You can also thump Beaver State bump the relay to see if the winnow kicks on. You fanny listen to the relay to see if it "clicks" when it is energized, only that doesn't mean the electrical relay is good – it can "click" and still not deliver power to the fan.
What Does a Cooling Devotee Relay Do?
The cooling fan electrical relay is an electromagnetic electrical switch that controls the major power provide to the engine's cooling system fans. It ensures that the muscularity-intensive devices only run when needed, usually when the vehicle is immobile.
When the engine temperature approaches unsafe levels, the vehicle's computer or temperature switch turns on the cooling winnow relay. The activated relay completes a circuit, allowing an electric current to flow through it and reach the cooling fans.
To learn more about how fan relays (and relay race, in general) put to work in the engine cooling system, read our in-profoundness explanation here.
Divergent Types of Cooling system Sports fan Relays
There are several types of cooling fan relays. Their main difference of opinion involves the winding armature that they use to sodding an electric tour.
Normally naked electrical relay
The most common type of relay uses an open armature. When the relay curlicue gets energized, the armature closes. The completed circuit allows the current to flow to the fan motor.
Normally closed relay
The opposite of the normally open relay, this type uses a drawn armature. Refreshful the relay coil opens the armature and completes the circuit.
Dual relay
This relay type uses two circuits, one of which employs an open armature while the other one has a closed armature. Thanks to its exercise of some armatures, a dual relay can conduct an electric current in both open and closed positions.
How Relays Work in the Cooling System
Ok, nearly people know that a relay is an electromagnetic switch. A casebook relay has a primary circuit that magnetizes a hand-build with a sword marrow – this turns the relay on, with the magnetism pull the secondary contacts together to cozy a circuit. These unessential terminals that carry the load of any the relay is switching.
Relay race are used for all kinds of jobs on a vehicle, from accessories to railway locomotive control components – the radiator cooling fan is one of the more crucial underhood components operated by a relay, or sometimes by two relay race. Fan relays typically carry from 30 to 50 amps, because fans consume much of current.
Everybody knows most vehicle engines are liquid cooled. Circulating coolant absorbs burning heat from the block and the cylinder head by conductivity, then carries the heat away by convection to the radiator, where the heat is discharged from runty tubes into particularly organized fins positioned and so that air will decease through and carry the heat out. The radiator is technically referred to as a "heat exchanger" because that's what it does.
The vehicle air conditioner has a electrical condenser – another heat money changer commonly affixed in breast of the radiator – that as wel requires airflow – sometimes thither volition be two fans for this cause, and those fans may run at a lower speed at the same meter, at full speed simultaneously, operating room one fan Crataegus oxycantha run while the other fan doesn't.
Vehicles either hold a module dominant rooter speeds or those with 2 fans often use 2 or 3 relays working together so that the fans can run in series (low cannonball along, rending the voltage and running slower) in parallel (both fans receiving chuck-full system voltage at the same time), or once more, just indefinite of the two fans might be energized sometimes, dependant on prevailing conditions.
Driving toss off the highway, zephyr naturally passes through the radiator, but when the vehicle is posing in traffic Oregon parked and squirting, the fan (belt driven or electric or one of each on some vehicles) draws air through the radiator to reduce the temperature of the coolant, which then returns to the block and the head to absorb additional heating plant. This is the short version of how a cooling whole works.
For a many self-contained discussion of the engine cooling system, read our article here.
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2003 Pontiac Grand Prix Cooling Fans Not Working
Source: https://www.carparts.com/blog/bad-cooling-fan-relay-symptoms/